Question

A 85 kg diver falls from rest into a swimming pool from a height of 4.6 m. It takes 1.66 s for the diver to stop after entering the water.

1.Find the speed [m/s] at which the diver enters the water? Submit Answer Tries 0/4

2.Find the magnitude of the average force exerted on the diver during that time (When she enters the water).

Can you please show work? Thank you

Answer 1

1.solution

v² = v₀² + 2*a*s
a = acceleration due to gravity (9.8 m/s^2)
v₀ = initial velocity (0, cause he just jumped)
s = distance he fell (4.6 m)
v = how fast he was going at the end of his fall

v² = 2*9.8*4.6m
v = 9.49 m/s

2.

now we start over with time 0 being the time when he hits the water, thus v₀ is now 9.49 m/s

v = 0 because it says he stops after the 1.66 s

v = v₀ + a*t
0 = 9.49 + a*1.66
a = - 5.72 m/s^2

so now we have acceleration, and we know mass

F = ma = 85.0 * -5.72 = - 486.20N

magnitude of F = 486.20N